IB Chemistry Stoichiometry multiple choice Past papers based

Front

What is stoichiometry?

Back

Stoichiometry is the branch of chemistry that deals with the calculation of reactants and products in chemical reactions based on the conservation of mass.

Front

Define Avogadro's constant.

Back

Avogadro's constant is the number of particles (atoms, molecules, ions) in one mole of a substance, approximately 6.022 x 10^23.

Front

What is the formula to calculate the number of moles?

Back

Number of moles = Mass (g) / Molar mass (g/mol).

Front

How do you calculate the percentage yield of a reaction?

Back

Percentage yield = (actual yield / theoretical yield) x 100%.

Front

What is the relationship between pressure, volume, and temperature in gases?

Back

According to the ideal gas law, PV = nRT, where P is pressure, V is volume, n is number of moles, R is the gas constant, and T is temperature in Kelvin.

Front

What is the molarity of a solution?

Back

Molarity (M) is the number of moles of solute per liter of solution.

Front

How many ions are present in 1 mole of NaCl?

Back

1 mole of NaCl contains 2 moles of ions (1 Na+ and 1 Cl-).

Front

What happens to the pressure of a gas if both its volume and temperature are doubled?

Back

According to Boyle's Law and Charles's Law, if both volume and temperature are doubled, the pressure remains constant.

Front

What is the decomposition reaction of Calcium Carbonate?

Back

CaCO3 (s) → CaO (s) + CO2 (g).

Front

How do you determine the number of ions in a compound like MgCl2?

Back

MgCl2 contains 3 ions: 1 Mg2+ ion and 2 Cl- ions.